[Oxytocin as a putative factor in the control of periodic and synchronized neurosecretory bursts of oxytocinergic cells (author's transl)].
During suckling, the intramammary pressure and the electrical activity of oxytocinergic cells in the paraventricular nucleus were recorded simultaneously in urethane-anaesthetized Rats. Injection of an oxytocin antagonist (1 microliter d(CH2)5OVT 10(-3) or 10(-4) M) into the 3rd ventricle, inhibited both frequency and amplitude of neurosecretory bursts and milk-ejections. The same effect was observed when the milk-ejection reflex was previously activated by the intraventricular injection of oxytocin (1 microliter--10(-6) M). Thus, oxytocin might regulate the frequency and amplitude of oxytocinergic cells' neurosecretory bursts and could be involved in their synchronism.
D000818:Animals; D005260:Female; D006801:Humans; D007276:Injections, Intraventricular; D007774:Lactation / Q000187:drug effects*; D008321:Mammary Glands, Animal / Q000187:drug effects / Q000502:physiology*; D008893:Milk Ejection / Q000187:drug effects*; D010121:Oxytocin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000502:physiology*; D011247:Pregnancy
D010121:Oxytocin; C008357:oxytocin, 1-beta-mercapto-beta, beta-diethylpropionic acid-Leu(4)-
L'ocytocine facteur possible du contrôle hypothalamique de l'activation périodique et synchrone des neurones ocytocinergiques pendant la têtée.